Anode support member and bipolar separator for use in a fuel cell assembly and for preventing poisoning of reforming catalyst

ABSTRACT

An anode support for supporting an anode electrode in a fuel cell assembly in which the anode support has a first support member formed of a porous non-wettable material and a second support member abutting and joined with the second member and having a plurality of through openings. Also disclosed is a bipolar separator having an electrolyte barrier over predetermined limited portions of its outer surface so as to prevent or retard electrolyte creeping.

BACKGROUND OF THE INVENTION

This invention relates to fuel cells and, in particular, to a bipolarseparator plate and anode side hardware design for use in moltencarbonate fuel cells.

A fuel cell is a device which directly converts chemical energy storedin hydrocarbon fuel into electrical energy by means of anelectrochemical reaction. Generally, a fuel cell comprises an anode anda cathode separated by an electrolyte, which serves to conductelectrically charged ions. Molten carbonate fuel cells (“MCFCs”) operateby passing a reactant fuel gas through the anode, while oxidizing gas ispassed through the cathode. In order to produce a useful power level, anumber of individual fuel cells are stacked in series with anelectrically conductive separator plate between each cell.

In internally reforming fuel cells, a steam reforming catalyst is placedwithin the fuel cell stack to allow direct use of hydrocarbon fuels suchas methane, coal gas, etc. without the need for expensive and complexreforming equipment. Two different types of internal reforming have beenused. Direct internal reforming is accomplished by placing the reformingcatalyst within the active anode compartment of each fuel cell. Thereforming catalyst in direct internal reforming fuel cells is typicallyplaced in an anode current collector and is available to reform fuel gaswith steam formed by the electrochemical reactions of the fuel cell andcan result in very high reforming efficiency and fuel utilization.

However, direct internal reforming fuel cells experience a decay in thecatalytic activity of the reforming catalyst. More particularly, overthe operating life of the fuel cell, the molten carbonate electrolytestored in the anode electrode of the cell, wets the abutting anodecurrent collector to expose and eventually poison the reforming catalyststored in the current collector. When the reforming catalyst is poisonedby the electrolyte, it is no longer able to perform the reformingreaction with the hydrocarbon fuels to generate sufficient hydrogen fuelfor the anode reaction. The poisoning of the reforming catalyst thusreduces the reforming and electrical efficiencies of the fuel cell.

To reduce electrolyte wetting of the anode current collector,conventional systems have employed a corrugated anode current collectorwhich can act as a barrier to shield the reforming catalyst from theelectrolyte. A non-wettable barrier between the anode and the anodecurrent collector, such as an anode support member, has also been usedto impede the wetting of the anode current collector and the creepage ofthe electrolyte toward the reforming catalyst. For example, U.S. Pat.No. 5,558,948 discloses a support member in a form of a perforated platemember made from a metallic corrosion resistant material. Otherconventional systems have employed anode support members in the form ofan expanded mesh, a wire mesh, or a porous sintered powder bed (U.S.Pat. No. 6,719,946). An anode support member constructed of a highporosity reticulated foam material has also been disclosed (U.S. Pat.No. 6,379,883). Non-wettable materials used to form such anode supportmembers typically include nickel, copper or other materials which arestable in the fuel-reducing atmosphere.

To further assist in retarding the creepage of the electrolyte,conventional systems have also employed a bipolar separator plate with aprotective coating on the plate or on portions of the plate forming wetseal regions. Such protective coating is typically formed from Al orAl/Fe (JP Patent Application No. 09-025822), and is applied to the wetseal portions of the plate by thermal spraying (JP Patent ApplicationNos. 09-025822 and 07-295276), high velocity oxy-fuel flame spraying(U.S. Pat. No. 5,698,337), aluminum painting, ion vapor deposition ormolten aluminum dip-coating (JP Patent Application No. 07-230175). Forexample, U.S. Pat. No. 6,372,374 discloses a bipolar separator platedesign which uses a stainless steel center sheet and wet-seal pocketmembers fabricated from stainless steel with aluminum protectivecoating. In the '374 patent, the wet-seal pocket members are welded tothe center sheet and aluminum is included in the weld material in a formof Al-containing filler wires. The separator plate and the anode currentcollector can also be coated with nickel or copper by electrolyticplating, cladding or vacuum deposition so as to further retard theelectrolyte creepage to the reforming catalyst. For example, U.S. Pat.No. 6,698,337 discloses a bipolar separator plate comprising Ni-cladstainless steel.

While the above methods have been successful in slowing down the rate ofelectrolyte creepage, these methods suffer from a number ofdisadvantages. The conventional anode support members, when used to forma barrier between the corrugated current collector and the anodeelectrode, have been unable to provide sufficient mechanical support forthe anode electrode. This results in waviness of the anode electrodecausing insufficient electrical contact between the anode electrode andthe abutting electrolyte matrix. The aluminum coating on the wet-sealpocket members of the separator plate is oxidized during the fuel celloperation and the surface of the wet-seal pocket members of the platebecomes wettable by the electrolyte. This allows the electrolyte tocreep along the external surface of the pocket members and toward theanode current collector and the reforming catalyst through fuel inletand outlet edges of the separator plate.

Moreover, the coating or plating processes to coat the wet-seal pocketmembers of the separator plate or the anode current collector withnickel or copper are expensive and significantly increase the fuel cellsystem manufacturing costs. The conventional electrolytic platingprocess used to coat the wet seal pocket members or the currentcollector can also result in non-uniform thickness of the coatedportions of the wet seal pocket members. Such non-uniformity inthickness causes flow and pressure mal-distribution within the fuel cellsystem as well as insufficient electrical contact between the fuel cellcomponents.

It is therefore an object of the present invention to provide a fuelcell assembly including an anode support, an anode current collector anda separator plate which overcomes these disadvantages.

It is also an object of the present invention to provide an improvedanode support member which further reduces the electrolyte wicking rateto the reforming catalyst so as to prolong the catalyst life andprovides improved mechanical support for the anode.

SUMMARY OF THE INVENTION

In accordance with certain of the embodiments of the invention describedherein, the above and other objectives are realized in an anode supportfor supporting an anode electrode in a fuel cell assembly, comprising afirst support member comprised of a porous non-wettable material and asecond support member comprised of a non-wettable metallic memberincluding a plurality of through openings. The first support memberabuts and is joined with the second support member. The first and secondsupport members each can comprise at least one of Ni, Cu, Ni alloy andCu alloy.

More particularly, in the some forms of the invention, the first supportmember comprises one of a high porosity reticulated foam material and aporous sintered powder bed, while the second support layer comprises oneof a wire mesh, an expanded wire mesh and a perforated plate member. Inthese forms of the invention, the first support member can have aporosity of less than 70% and a mean pore size of at least 20 μm, andthe thickness of the first support layer can be at least 2 mils. Also inthese forms of the invention, the second member can have a thickness ofat least 5 mils, while the through openings in the second support membercan be 20 mils or smaller in diameter and comprise at least 40% of anarea of the second support member. The first support member can bejoined with the second support member using a lamination process.

The first support member can form a first surface of the support and thesecond support member a second surface of the support. The first surfaceof the support is adapted to abut the anode electrode and the secondsurface is adapted to abut an anode current collector in a fuel cellassembly.

The above and other objectives are also realized in a bipolar separatorhaving opposing first and second surfaces compatible with fuel gas andoxidant gas, respectively, and also having first and second opposingends and third and fourth opposing ends. The bipolar separator alsocomprises first, second, third and fourth pocket members, with the firstand second pocket members being situated adjacent the first and secondopposing ends of the plate member and extending outward of the firstsurface and then facing each other and the third and fourth pocketmembers being situated adjacent the third and fourth opposing ends ofthe plate member and extending outward of the second surface and thenfacing each other.

The outer surface of the bipolar separator includes first and secondouter surface parts formed by the outer surfaces of the third and fourthpocket members, respectively, and an electrolyte barrier is arranged ona limited portion of the first outer surface part and a limited portionof the second outer surface part.

In certain of the embodiments of the invention, the electrolyte barrieris a non-wettable material and can be in the form of a weld bead, foilor coating welded or applied to the respective limited portions of thefirst or second outer surface parts. Particular, usable non-wettablematerial might be Ni, Cu, Ni alloy and Cu alloy. The electrolyte barriermay also include a filler, such as a welding filler rod. An example ofthe thickness of the electrolyte barrier is a thickness in the range ofbetween 10 and 100 μm and an example of the width of the barrier is atleast 0.1 inches.

In certain forms of the invention, the third pocket member includes aback extension aligned with an end extension at the third end of theplate member, and peripheries of the back extension and the endextension form a wet-seal edge. Similarly, the fourth pocket memberincludes a back extension aligned with an extension at the fourth end ofthe plate member, and peripheries of the back extension and the secondend extension form a wet-seal edge. The wet-seal edges are included inthe limited portions of the first and second outer surface parts of theouter surface of the bipolar separator and the electrolyte barrier canbe applied or welded to the wet-seal edges. Also, in the aforesaid formsof the invention, third and fourth welds can be used to join the thirdand fourth pocket members, respectively, to the end extensions of thethird and fourth ends of the plate member. Additionally, the first andsecond pocket members include back extensions aligned with third andfourth end extensions at the first and second ends of the plate member,and welds join these back extensions and the end extensions.

A fuel cell assembly employing the anode support member and the bipolarseparator plate is also disclosed.

BRIEF SUMMARY OF THE DRAWINGS

The above and other features and aspects of the present invention willbecome more apparent upon reading the following detailed description inconjunction with the accompanying drawings, in which:

FIG. 1 shows a cross-sectional view of a fuel cell assembly of a moltencarbonate fuel cell with direct internal gas reforming;

FIG. 2 shows a detailed cross-sectional view of a portion of theassembly of FIG. 1 encircled as “1A” in FIG. 1;

FIG. 3A shows a photograph of an anode electrode supported by the anodesupport of FIG. 2;

FIG. 3B shows a photograph of an anode electrode supported by aconventional wire mesh anode support;

FIG. 4 shows a perspective view of an illustrative construction of thebipolar separator plate shown in FIG. 1;

FIG. 5 shows a detailed cross-sectional view of a fuel outlet endportion of the fuel cell assembly of FIG. 1 including the bipolar plateof FIG. 4.

DETAILED DESCRIPTION

FIG. 1 shows a cross-sectional view of a fuel cell assembly 1 of amolten carbonate fuel cell with direct internal gas reforming. The fuelcell assembly 1 includes an anode electrode 2 and a cathode electrode 3separated by, and in direct contact with, an electrolyte matrix 4. Theelectrolyte matrix 4 is filled with carbonate electrolyte, andadditional electrolyte is provided in the pores of the anode and cathodeelectrodes.

The assembly 1 also includes an anode support 5 abutting the anodeelectrode 2 and a corrugated anode current collector 6 abutting thesupport member 5 on the anode side of the assembly and a cathode currentcollector 8 abutting the cathode electrode 3 on the cathode side of theassembly 1. As described in further detail below, the anode support 5provides mechanical support for the anode electrode 2 and also acts as abarrier to electrolyte creeping from the anode electrode to the anodecurrent collector 6.

As shown, the anode side of the fuel cell assembly 1 is separated froman adjacent fuel cell assembly by a first bipolar plate 7, while thecathode side of the assembly 1 is separated from another adjacent fuelcell assembly by a second bipolar plate 9. As also shown, the anodecurrent collector 6 houses a direct reforming catalyst 11 in the spacesor passages defined by the corrugations of the current collector 6between the current collector 6 and the bipolar plate 7. In this way,the anode current collector acts as an additional barrier to electrolytecreeping to protect the reforming catalyst 11 from poisoning by theelectrolyte.

FIG. 2 shows a detailed cross-sectional view of a portion of theassembly of FIG. 1 encircled as “1A” in FIG. 1. In particular, FIG. 2shows a more detailed view of the anode electrode 2 and the anodesupport 5 shown in FIG. 1. The anode electrode 2 comprises a porousmaterial with a high surface area, such as a nickel alloy. For example,the anode electrode 2 may be formed from Ni—Al or Ni—Cr powder, in whichAl and Cr are used as stabilizing agents to enhance the mechanicalstrength of the electrode 2 and to prevent excessive anode sintering atfuel cell operating temperatures, i.e. 500-700° Celsius. The anodeelectrode 2 may further include organic binders such as an acrylicpolymer. During the operation of the fuel cell assembly 1, the anodeelectrode 2 is filled with carbonate electrolyte, which takes up between5 and 50% of the void volume of the electrode. In order to reducemanufacturing costs, the anode electrode is preferably a thin anodeelectrode having a thickness between 2 and 10 mils.

As shown, the anode electrode 2 abuts the anode support 5, whichprovides mechanical support for the anode electrode 2 and prevents theelectrolyte in the anode 2 from creeping to the anode current collector(not shown for clarity and simplicity in FIG. 2) and the reformingcatalyst stored in the current collector. The anode support 5 comprisesa plurality of supporting members including a first support member 5 aand a second support member 5 b. Both the first and the secondsupporting members 5 a, 5 b comprise non-wettable metallic materialssuch as nickel, copper or alloys of nickel or copper. Other non-wettablematerials which are stable in the fuel-reducing atmosphere may also beused to form the support members of the support 5. For example, nickelor chromium alloys such as nickel-chromium or nickel-aluminum, andmixtures thereof, are suitable materials for forming the support members5 a, 5 b of the support 5. The first and second support members 5 a, 5 bare joined with one another by laminating in a press or a pinch rolleror using any other suitable technique.

As shown in FIG. 2, the first support member 5 a is disposed in anabutting relationship with the anode electrode 2 and is formed as aporous member. For example, the high porosity reticulated foam disclosedin U.S. Pat. No. 6,379,833 or the porous sintered powder bed disclosedin U.S. Pat. No. 6,719,946 are suitable for use as the first supportmember 5 a. The porosity of the first support member 5 a is preferablyless than 70% so that the member 5 a has sufficient creep strength, andthe mean pore size of the member 5 a is preferably at least 20 μm. Whenthe first support member 5 a is joined with the second support member 5b, the final compressed thickness of the first support member 5 a can beat least 2 mils.

The second support member 5 b follows and abuts the first support member5 a and is formed as a member having a plurality of through openings. Inparticular, the second support member 5 b can be formed as a perforatedplate, as a wire mesh or an expanded mesh member. The second supportmember 5 b can have a thickness of at least 5 mils and through openingswhich comprise at least 40% of its total area, with the opening sizebeing 20 mils or less in diameter.

A photograph of an anode electrode 2 supported by the anode support 5 ofFIG. 2 is shown in FIG. 3A, while a photograph of an anode supported bya conventional wire mesh anode support is shown in FIG. 3B. As can beseen in FIG. 3B, the conventional wire mesh support has an uneven orwavy surface, and the anode electrode directly abutting the support,conforms to this wavy surface of the support member. In FIG. 3A, theanode support 5 of FIG. 2, as discussed above, has the metallic foamsupport member 5 a disposed between the wire mesh support member 5 b andthe anode electrode 2. The foam support member fills the spaces betweenthe surfaces of the anode electrode 2 and the wire mesh support member 5b, thus providing additional mechanical support to the anode electrode2. This added mechanical support results in a smoother anode surfaceabutting, and contacting with, the electrolyte matrix 4, thus improvingthe electrical contact between the anode electrode 2 and the matrix 4.

Surface roughness of the surface abutting the electrolyte matrix 4 ofthe anode electrode supported by the anode support 5 shown in FIG. 3Awas measured using a profilometer and compared with the surfaceroughness of the surface abutting the matrix of the anode electrodesupported by the conventional wire mesh support as shown in FIG. 3B. Inparticular, the surface profilimetry measurements were taken using 6.5ml anodes supported by the conventional wire mesh support member, 6.5 mlanodes supported by 25 mil and 20 mil foam and wire mesh supportmembers, and 4.5 ml anodes supported by 18 mil foam and wire meshsupport members. These profilometer measurements of the anode surfaceroughness in microinches are summarized in Table 1, as follows: TABLE 16.5 ml Anode with 6.5 ml Anode with 6.5 ml Anode with 4.5 ml Anode withConventional Mesh 25 mil Foam-Mesh 20 mil Foam-Mesh 18 mil Foam-MeshSupport Member Support Support Support 1 157 94 91 87 2 145 77 108 96 3130 87 84 97 4 145 80 94 109 5 156 81 92 105 Avg 147 84 94 99

As shown in Table 1, the surface roughness of the anode electrode wassignificantly reduced by using the additional foam member 5 a in support5 for supporting the electrode. Such a reduction of surface roughness ofthe anode electrode surface indicates that the anode is better supportedmechanically by the support member and that the electrical contactbetween the anode electrode and the electrolyte matrix is improved.

As discussed above, in addition to providing support for the anodeelectrode 2, the anode support 5 slows down the electrolyte creepagefrom the electrolyte matrix 4 and the anode electrode 2 to the reformingcatalyst 11 stored in the anode current collector 6. In particular, theanode support 5 forms a physical barrier between the anode electrode 2and the anode current collector 6. The non-wettability of the materialscomprising the anode support 5 further prevents or reduces electrolytecreepage to the reforming catalyst 11.

Electrolyte creeping from the matrix to the reforming catalyst can alsobe reduced by providing a non-wettable barrier on pre-selected limitedportions of the outer surface of each of the bipolar separator plates 7,9. FIG. 4 shows a perspective view of an illustrative construction ofthe bipolar separator plate 7 shown in FIG. 1. As can be appreciated,the construction of the bipolar separator 9 is substantially the same asthat of the bipolar separator 7. The general construction of the bipolarseparator plate 7 is similar to the bipolar separator plate disclosed inthe commonly assigned U.S. Pat. No. 6,372,374, the entire disclosure ofwhich is incorporated herein by reference.

As shown in FIG. 4, the bipolar plate 7 includes a central plate member13 having first and second surfaces 13A and 13B which are compatiblewith oxidant and fuel gases, respectively. In this illustrative example,the plate member 13 includes four opposing ends, with opposing ends 13Dand 13C corresponding to fuel inlet and fuel outlet ends of the fuelcell assembly, respectively, and opposing ends 13E and 13F formingoxidant inlet and oxidant outlet ends of the assembly, respectively.Each end 13C-13F of the of the plate member 13 has an end extension13EXT and a pocket member is formed or arranged adjacent each endextension.

As shown in FIG. 4, pocket members 14, 15 are situated adjacent opposingend extensions of plate ends 13C, 13D and extend outward of the firstsurface 13A of the plate member 13 and then toward each other.Similarly, the pocket members 16, 17 are situated adjacent the otheropposing end extensions of the ends 13E, 13F and extend outward of thesecond surface 13B of the plate member 13 and then toward each other.

As in the '374 patent, the plate member 13 is preferably formedseparately from the pocket members 14-17, and the pocket members 14-17are joined with the plate member 13 by welding or any other suitableconventional technique. The plate member 13 can be formed from anaustenitic high-temperature stainless steel which preferably includes18-26 wt % Cr and 11-33 wt % Ni. For example, stainless steel 310, 347or 309 are suitable for forming the plate member 13. The pocket members14-17 can, in turn be formed from stainless steel, which can be coatedor clad with aluminum to protect the pocket members from corrosion bythe reducing and oxidizing gases. As will be discussed below, anon-wettable material or coating is provided only on predetermined orpre-selected limited portions of the outer surface of the bipolar plate7.

As shown in FIG. 4, each pocket member 14, 15, 16, 17 includes a topwall 18A, side walls 18B, 18C, a back wall 18D and a back extension 18E.The top wall 18A of the pocket members 14, 15 faces the first surface13A, which is oxidant gas compatible, while the top walls 18A of thepocket members 16, 17 face the second surface 13B, which is fuel gascompatible. In this way, the pocket members 14, 15 are on the oxidantside of the bipolar plate 7, while the pocket members 16, 17 are on thefuel side of the bipolar plate 7. The pocket members 14-17 act as railsand the surfaces of these rails form wet seal areas with the abuttingelectrolyte matrix. These wet seal areas keep the oxidant gas and thefuel gas from leaking from the cathode and the anode, respectively, soas to prevent gas crossover and escape of these gases from the fuel cellassembly.

In the example of FIG. 4, the back extensions 18E of the pocket members14-18 are welded to the end extensions 13EXT of the corresponding ends13C-13F of the plate 13. This is shown clearly in FIG. 5 for the backextension of the pocket member 14. More particularly, FIG. 5 shows across-sectional view of a fuel outlet end portion of the fuel cellassembly of FIG. 1 using the bipolar plate 7 of FIG. 4. Specifically,FIG. 5 shows a cross-sectional view of the fuel outlet end 13C of theplate member 13 and the oxidant side pocket member 14 formed adjacentthe fuel outlet end 13C. As can be appreciated, the fuel inlet endportion of the fuel cell assembly which includes the pocket member 15,has a substantially identical construction as the fuel outlet endportion shown in FIG. 5.

As discussed above with respect to FIG. 4 and as can be seen in FIG. 5,the pocket member 14 includes the top wall 18A, the back wall 18D andthe back extension 18E. The side walls 18B, 18C of the pocket member 14are not visible in FIG. 5. The back extension 18E co-extends with theend extension 13EXT of the fuel outlet end 13C of the plate member 13and is welded thereto. The edge of the back extension 18E and the edgeof the end extension of the fuel outlet end 13C form a wet seal edge 7Aof the bipolar plate.

As can be seen, the top wall 18A of the pocket member 14 is in directcontact with the electrolyte-filled matrix 4. During fuel celloperation, as indicated by an arrow in FIG. 5, the electrolyte creepsfrom the matrix 4 along the outer surface 14A of the pocket member 14which outer surface forms a first part of the outer surface of theseparator 7. The electrolyte continuously creeps along the outer surface14A of the pocket member 14 to the end of the edge of the surface. Fromthere, the electrolyte creeps onto the edge of the outer surface of theback extension 13EXT of the end 13C of the plate 13. From this edge itcontinues to creep on this outer surface which is forms the anode sidesurface 13A of the plate member 13.

The surface 13A is in direct contact with the anode current collector 6housing the reforming catalyst 11. Accordingly, continued creep of theelectrolyte results in the electrolyte reaching the catalyst, therebypoisoning the catalyst. Moreover, as discussed above, conventionalaluminum coatings on the outer surface 14A of the pocket member 14oxidize during fuel cell operation and become wettable, thus allowingthis electrolyte creep and catalyst poisoning to take place.

As also mentioned above, the bipolar plate 7 includes a non-wettableelectrolyte barrier provided at pre-selected limited portions of firstand second parts of the outer surface of the separator to retardelectrolyte cereepage and, therefore, prevent poisoning of the reformingcatalyst. In the illustrative case shown in FIG. 5, the electrolytebarrier is identified at 20 and is provided to a portion of the outersurface 14A of the pocket member 14 (first part of the outer surface ofthe separator) and, in particular, to the outer surface of the edge ofthe back extension 18E of the pocket member. It is also applied to theouter surface of the edge of the end extension 13EXT of the end 13C ofthe plate 13. The barrier 20 thus covers the wet seal edge 7A of thebipolar plate 7.

The electrolyte barrier 20 can comprise a non-wettable material, such asNi or Cu, or an alloy of Ni or Cu, which is stable in the fuel cellatmosphere. In one example, the non-wettable barrier 20 is formed as aweld bead comprising Ni or Cu material, applied to the aforementionededges forming the wet seal edge 7A. Alternatively, the electrolytebarrier 20 may formed as a foil welded to such edges or as anon-wettable coating applied to such edges by cladding, plating, thermalspraying, vacuum deposition or any other known methods. When thenon-wettable barrier is formed from a foil or coating, additionalnon-wettable filler material, such as an Ni or Cu welding filler rod,may also be applied to surface of the edges to increase the Ni or Cucontent of the barrier. A typical thickness of the electrolyte barrier20 is 10 to 100 μm and typical width of the barrier is greater than 0.1inches.

As also shown in FIG. 5, the electrolyte barrier 20 may further comprisean additional non-wettable coating 20A applied to an additional portionof the outer surface 14A of the pocket member 14 along the backextension 18E. This additional coating further slows down the creepingor wicking of the electrolyte toward the wet seal edge 7A. In the caseillustrated, the coating 20A extends from the wet seal edge 7A along apredetermined portion of the width of the back extension 18E. A typicalwidth of the non-wettable coating 20A is a width greater than 0.03inches and typical coating materials are Ni, Cu, Ni alloy and Cu alloy.The coating 20A can be applied to the back extension 18E using anysuitable conventional method such as cladding, plating, thermal sprayingor vacuum deposition.

Because the barrier 20 including the non-wettable coating 20A is appliedonly to limited a portion of the outer surface of the pocket member 14,rather than to the entire outer surface of the pocket member 14, themanufacturing cost of the bipolar separator plate 7 is reduced. This isaccomplished without affecting the ability of the separator to preventelectrolyte creeping toward the reforming catalyst.

As mentioned above, the fuel inlet end of the bipolar plate, whichincludes the other pocket member 15 adjacent the fuel inlet end 13D ofthe plate member 13, has a substantially an identical barrier applied toit at portion of its outer surface (the second part of the surface ofthe separator). The pocket members 16-17 on the fuel side of the bipolarplate 7, which also have similar constructions as the pocket members 14and 15, while they make include similar barriers as the pocket members14-15, do not require such barriers. Not using barriers with thesepocket members and using the barrier members only at the fuel inlet andoutlet ends of the bipolar plate 7, as above-described, can thereforeresult in additional cost savings in manufacturing the bipolar plate 7.

In all cases it is understood that the above-described arrangements aremerely illustrative of the many possible specific embodiments thatrepresent applications of the present invention. Numerous varied otherarrangements can be readily devised in accordance with the principles ofthe present invention without departing from the spirit and scope of theinvention.

1. An anode support for supporting an anode electrode in a fuel cellassembly, said anode support comprising: a first support membercomprising a porous non-wettable material; and a second support membercomprising a non-wettable metallic member having a plurality of throughopenings, wherein said first support member abuts and is joined withsaid second support member.
 2. An anode support in accordance with claim1, wherein said first support member comprises at least one of Ni, Cu,Ni alloy and Cu alloy.
 3. An anode support in accordance with claim 2,wherein said first support member comprises one of a high porosityreticulated foam material and a porous sintered powder bed.
 4. An anodesupport member in accordance with claim 3, wherein said first supportmember has a porosity of less than 70% and a mean pore size of at least20 μm.
 5. An anode support in accordance with claim 4, wherein athickness of said first support member is at least 2 mils.
 6. An anodesupport in accordance with claim 1, wherein said second support membercomprises one of a wire mesh, an expanded wire mesh, and a perforatedplate member.
 7. An anode support in accordance with claim 6, whereinsaid second support member comprises at least one of Ni, Cu, Ni alloyand Cu alloy.
 8. An anode support in accordance with claim 7, whereinsaid second support member has a thickness of at least 5 mils.
 9. Ananode support in accordance with claim 8, wherein said through openingsin said second support member are 20 mils or smaller in diameter andsaid openings comprise at least 40% of an area of said second supportmember.
 10. An anode support in accordance with claim 3, wherein saidsecond support member comprises one of a wire mesh, an expanded wiremesh, and a perforated plate member, said second support member isformed from at least one of Ni, Cu, Ni alloy and Cu alloy.
 11. An anodesupport member in accordance with claim 10, wherein said first supportmember is joined with said second support member using a laminationprocess.
 12. An anode support in accordance with claim 11, wherein saidfirst support member forms a first surface of said anode support andsaid second support member forms a second surface of said anode support,and said first surface is adapted to abut said anode electrode and saidsecond surface is adapted to abut an anode current collector of saidfuel cell assembly.
 13. A bipolar separator for use with a fuel cellcomprising: a plate member having opposing first and second surfacescompatible with fuel gas and oxidant gas, respectively, said platemember having first and second opposing ends and third and fourthopposing ends; first, second, third and fourth pocket members, saidfirst and second pocket members being situated adjacent said first andsecond opposing ends of said plate member and extending outward of saidfirst surface and then facing each other and said third and fourthpocket members being situated adjacent said third and fourth opposingends of said plate member and extending outward of said second surfaceand then facing each other; said bipolar separator having first andsecond outer surface parts formed by the outer surfaces of said thirdand fourth pocket members, respectively; and an electrolyte barriercomprising a non-wettable material situated on a limited portion of theouter surface of said third pocket member and a limited portion of theouter surface of said fourth pocket member.
 14. A bipolar separator inaccordance with claim 13, wherein: said limited portion of said outersurface of said third pocket member includes a surface portion at theend of said outer surface of said third pocket member closest said platemember; and said limited portion of said outer surface of said fourthpocket member includes a surface portion at the end of said outersurface of said fourth pocket member closest said plate member.
 15. Abipolar separator in accordance with claim 14, wherein said electrolytebarrier comprises one of a weld bead, a foil welded to and a coatingapplied to said limited portion of the outer surface of said thirdpocket member and to said limited portion of the outer surface of saidfourth pocket member.
 16. A bipolar separator in accordance with claim15, wherein said electrolyte barrier comprises at least one of Ni, Cu,Ni alloy and Cu alloy.
 17. A bipolar separator in accordance with claim16, wherein said electrolyte barrier further comprises a filler.
 18. Abipolar separator in accordance with claim 17, wherein said fillercomprises a welding filler rod.
 19. A bipolar separator in accordancewith claim 15, wherein said electrolyte barrier has a thickness of 10 to100 μm and a width of at least 0.1 inches.
 20. A bipolar separator inaccordance with claim 14, wherein: said electrolyte barrier comprisesone of a weld bead and a foil welded to said limited portion of theouter surface of said third pocket member and to said limited portion ofthe outer surface of said fourth pocket member; and said electrolytebarrier further comprises a non-wettable coating: applied to saidlimited portion of the outer surface of said third pocket member andextending from said one of said weld bead and said foil welded to saidlimited portion of said outer surface of said third pocket; and appliedto said limited portion of the outer surface of said fourth pocketmember and extending from said one of said weld bead and said foilwelded to said limited portion of said outer surface of said fourthpocket member.
 21. A bipolar separator in accordance with claim 14,wherein: said third pocket member includes a back extension aligned withan end extension at said third end of said plate member, edge surfacesof said back extension of said third pocket member and said endextension at said third end of said plate member forming a wet-sealedge, and and said fourth pocket member includes a back extensionaligned with an end extension at said fourth end of said plate member,edge surfaces of said back extension of said fourth pocket member andsaid end extension at said fourth end of said plate member forming awet-seal edge; and wherein the edge surface of the back extension ofsaid third pocket member forms a part of the limited portion of theouter surface of the third pocket member and the edge surface of theback extension of the fourth pocket member forms a part of the limitedportion of the outer surface of the fourth pocket member.
 22. A bipolarseparator in accordance with claim 21, wherein: said electrolyte barriercomprises one of a weld bead, a foil welded to and a coating applied tosaid limited portion of the outer surface of said third pocket memberand to said limited portion of the outer surface of said fourth pocketmember.
 23. A bipolar separator in accordance with claim 21: saidelectrolyte barrier comprises one of a weld bead and a foil welded tosaid limited portion of the outer surface of said third pocket memberand to said limited portion of the outer surface of said fourth pocketmember; and said electrolyte further comprises a non-wettable coating:applied to said limited portion of the outer surface of said thirdpocket member and extending from said one of said weld bead and saidfoil welded to said limited portion of said outer surface of said thirdpocket; and applied to said limited portion of the outer surface of saidfourth pocket member and extending from said one of said weld bead andsaid foil welded to said limited portion of said outer surface of saidfourth pocket member.
 24. A bipolar separator in accordance with claim21, wherein; said plate member is formed separately from said pocketmembers, said first pocket member includes a back extension aligned withan end extension at said first end of said plate member; and said secondpocket member includes a back extension aligned with an end extension atsaid second end of said plate member; and said back extensions of saidfirst, second, third and fourth pocket member are welded to the endextensions at the first, second, third and fourth ends of said platemember.
 25. A fuel cell assembly comprising: a fuel cell including ananode, a cathode and an electrolyte matrix disposed between said anodeand said cathode; an anode support abutting and supporting said anode,said anode support comprising: a first support member comprising aporous non-wettable material; and a second support member comprising anon-wettable metallic member having a plurality of through openings,wherein said first support member abuts and is joined with said secondsupport member.
 26. A fuel cell assembly in accordance with claim 25,further comprising: an anode current collector abutting said secondsupport member and forming a plurality of passages for passing fuel gasand storing a reforming catalyst therein; and a bipolar separatorabutting said anode current collector for separating said fuel cellassembly from an adjacent fuel cell assembly.
 27. A fuel cell assemblyin accordance with claim 25, wherein said first support member comprisesone of a high porosity reticulated foam material and a porous sinteredpowder bed, and said second support member comprises one of a wire mesh,an expanded wire mesh and a perforated plate member.
 28. A fuel cellassembly in accordance with claim 26, wherein: said first support memberhas a porosity of less than 70% and a mean pore size of at least 20 μm;said through openings in said second support member are 20 mils orsmaller in diameter and said openings comprise at least 40% of an areaof said second support member; and said first support member has athickness of at least 2 mils and said second support member has athickness of at least 5 mils.
 29. A fuel cell assembly in accordancewith claim 30, wherein said first support member is joined with saidsecond support member using a lamination process.
 30. A fuel cellassembly comprising: a fuel cell including an anode, a cathode and anelectrolyte matrix disposed between said anode and said cathode; ananode current collector abutting said anode and forming a plurality ofpassages for passing fuel gas and storing a reforming catalyst therein;and a bipolar separator abutting said anode current collector forseparating said fuel cell assembly from an adjacent fuel cell assembly,said bipolar separator comprising a plate member having opposing firstand second surfaces, said first surface being compatible with fuel gasand abutting said anode current collector and said second surface beingcompatible with oxidant gas and abutting said adjacent fuel cellassembly, said plate member having first and second opposing ends andthird and fourth opposing ends; first, second, third and fourth pocketmembers, said first and second pocket members being situated adjacentsaid first and second opposing ends of said plate member and extendingoutward of said first surface and then facing each other, and said thirdand fourth pocket members being situated adjacent said third and fourthopposing ends of said plate member and extending outward of said secondsurface and then facing each other; said bipolar separator having firstand second outer surface parts formed by the outer surfaces of saidthird and fourth pocket members, respectively; and an electrolytebarrier comprising a non-wettable material situated on a limited portionof the outer surface of said third pocket member and a limited portionof the outer surface of said fourth pocket member.
 31. A fuel cellassembly in accordance with claim 30, wherein: said limited portion ofsaid outer surface of said third pocket member includes a surfaceportion at the end of said outer surface of said third pocket memberclosest said plate member; and said limited portion of said outersurface of said fourth pocket member includes a surface portion at theend of said outer surface of said fourth pocket member closest saidplate member.
 32. A fuel cell assembly in accordance with claim 31,wherein said electrolyte barrier comprises a non-wettable materialcomprising at least one of Ni, Cu, Ni alloy and Cu alloy.
 33. A fuelcell assembly in accordance with claim 31, wherein said electrolytebarrier comprises one of a weld bead, a foil welded to and a coatingapplied to said limited portion of the outer surface of said thirdpocket member and to said limited portion of the outer surface of saidfourth pocket member.
 34. A fuel cell assembly in accordance with claim33, wherein said electrolyte barrier further comprises a filler.
 35. Afuel cell assembly in accordance with claim 34, wherein said fillercomprises a welding filler rod.
 36. A fuel cell assembly in accordancewith claim 33, wherein said electrolyte barrier has a thickness of 10 to100 μm and a width of at least 0.1 inches.
 37. A bipolar separator inaccordance with claim 31, wherein: said electrolyte barrier comprisesone of a weld bead and a foil welded to said limited portion of theouter surface of said third pocket member and to said limited portion ofthe outer surface of said fourth pocket member; and said electrolytebarrier further comprises a non-wettable coating: applied to saidlimited portion of the outer surface of said third pocket member andextending from said one of said weld bead and said foil welded to saidlimited portion of said outer surface of said third pocket; and appliedto said limited portion of the outer surface of said fourth pocketmember and extending from said one of said weld bead and said foilwelded to said limited portion of said outer surface of said fourthpocket member.
 38. A bipolar separator in accordance with claim 31,wherein: said third pocket member includes a back extension aligned withan end extension at said third end of said plate member, edge surfacesof said back extension of said third pocket member and said endextension at said third end of said plate member forming a wet-sealedge, and and said fourth pocket member includes a back extensionaligned with an end extension at said fourth end of said plate member,edge surfaces of said back extension of said fourth pocket member andsaid end extension at said fourth end of said plate member forming awet-seal edge; and wherein the edge surface of the back extension ofsaid third pocket member forms a part of the limited portion of theouter surface of the third pocket member and the edge surface of theback extension of the fourth pocket member forms a part of the limitedportion of the outer surface of the fourth pocket member.
 39. A bipolarseparator in accordance with claim 38, wherein: said electrolyte barriercomprises one of a weld bead, a foil welded to and a coating applied tosaid limited portion of the outer surface of said third pocket memberand to said limited portion of the outer surface of said fourth pocketmember.
 40. A bipolar separator in accordance with claim 38: saidelectrolyte barrier comprises one of a weld bead and a foil welded tosaid limited portion of the outer surface of said third pocket memberand to said limited portion of the outer surface of said fourth pocketmember; and said electrolyte further comprises a non-wettable coating:applied to said limited portion of the outer surface of said thirdpocket member and extending from said one of said weld bead and saidfoil welded to said limited portion of said outer surface of said thirdpocket; and applied to said limited portion of the outer surface of saidfourth pocket member and extending from said one of said weld bead andsaid foil welded to said limited portion of said outer surface of saidfourth pocket member.
 41. A bipolar separator in accordance with claim38, wherein; said plate member is formed separately from said pocketmembers, said first pocket member includes a back extension aligned withan end extension at said first end of said plate member; and said secondpocket member includes a back extension aligned with an end extension atsaid second end of said plate member; and said back extensions of saidfirst, second, third and fourth pocket member are welded to the endextensions at the first, second, third and fourth ends of said platemember.